Under the same style as BugMeNot, place in which a user shares his information to accede to commercial sites (magazines or online diaries for example); now there has been thrown RetailMeNot.
RetailMeNot is a free service that helps to find discount coupons for online services. Simply coarse to write a web address and RetailMeNot will show a list of coupons, which have been provided by other users of the web.
Link: RetailMeNot